A reel-life wrestling match ended in a real-life scare for Diane Keaton yesterday when she was injured filming a scene for “Morning Glory” on Sixth Avenue in Midtown. Keaton, 63, was in an inflatable sumo suit, but the padding didn’t help when a real sumo wrestler gave her a belly bump, knocking her to the ground. She lay there for a half-hour until medics put her neck in a brace and put her in an ambulance. She was “in good health” later in the day, a Paramount statement said.